1. Technical Field
The invention relates to a toner for electrostatic image development, a method of producing the same, an electrostatic image developer, a toner cartridge, a process cartridge, and an image forming apparatus.
2. Related Art
Generally, according to electrophotographic methods, a latent image is formed electrically by various units on the surface of a photoreceptor (latent image holding member) which utilizes a photoconductive substance, and the formed latent image is developed with a toner to form a toner image, and thereafter this toner image is transferred onto the surface of an image receiving material such as paper or the like, if necessary via an intermediate transfer material. The transferred image is subjected to a fixing process such as heating, pressurizing, heat-pressurizing, or the like, such that a fixed image is formed. Toner which remains on the surface of the photoreceptor is generally cleaned with a blade in a cleaning step.
As a fixing technique for fixing a toner image which has been transferred onto a surface of an image receiving material, a thermal roll fixing method wherein an image receiving material having a toner image transferred thereon is inserted between a pair of rolls composed of a heating roll and a pressure roll to fix the image is commonly used. In addition, as a similar technique, a technique in which one or both of the rolls is substituted with a belt is also known. In these techniques, an image that is fixed fast can be obtained at high speed and with high energy efficiency, because of direct contact with the image, as compared with other fixing methods.
With increased demand for reduction of the power required for image formation in recent years, techniques for developing a toner at low temperatures aimed at saving electric power consumed in the fixing process, which consumes a certain amount of the energy used in image formation, and at broadening the conditions for fixing, are increasingly necessary.
In a toner containing a crystalline polyester resin, however, the crystalline polyester resin is poor in resin strength, and upon exposure to the surface of the toner, is liable to filming (adhesion as a film) on the surface of a development roll or a photoreceptor, often leading to image quality defects in a short time, particularly in a high-speed machine using a high process speed.